At 18:00 8/1/04, Marco Kobbenbring wrote:
The problem is that when I play back the wave files, there appear short klicks with the onset of every tone of the file. They are very inconspicuous, however, under experimental conditions they become audible. I used fade in and out for every tone, so the transition from one tone to the other is smooth.
You are right to use fade-in/out. Are your fades going to infinity or only to, say, -40dB? - you mention that the click is "inconspicuous". Perhaps you are using a lot of amplification to detect the clicks? Two more possibilities: you might have made the recordings at a low level and what you are hearing is the start-of-playback noise as the audio replay synchronizes - usually inaudible or masked by signal. Another possibility is that the recordings contain a dc-offset which can cause a 'plop' sound as the playback starts and ends. I am not sure why this should happen on a digitally-generated tone but I have seen/heard this before and have used a feature in Cool Edit to remove the offset (one of the options under 'normalize' in my old '96 edition). Good luck! Neil Adams